The ability to stand, walk, or otherwise support oneself in an upright position requires that the individual be capable of transmitting weight forces through his/her legs. This, in turn, requires that the individual be capable of straightening his/her legs so as to align the upper portion of the leg (i.e., the portion of the leg above the knee) with the lower portion of the leg (i.e., the portion of the leg below the knee). Unfortunately, some individuals are either unable to control physical movement of their legs or have very limited control of their legs, thereby making it quite arduous for these physically limited individuals to align the femur and tibia of the leg in the manner required for supporting the weight of the body. This physical handicap may be attributable to muscle weakness, muscle deterioration or damage, or a host of other problems. Whatever the cause, it is very difficult, if not impossible, for these physically handicapped individuals to stand, walk or otherwise support their weight while in an upright position without the use of some type of orthopedic aid.
FIG. 1 illustrates a typical known medical device worn by a physically handicapped individual in order to permit some amount of mobility and stability. As shown, the device 10 includes a pair of first lower rigid metal bars 12, 14 that are connected to a respective pair of second lower rigid metal bars 16, 18 by way of a suitable connecting arrangement such as rivets 20. A pair of first upper rigid metal bars 22, 24 are connected to a respective pair of second upper rigid metal bars 26, 28 by a suitable connecting arrangement such as rivets 30. The second lower rigid bars 16, 18 are connected to the first upper rigid bars 22, 24, respectively, by a joint connection 32 (only one of which can be seen in FIG. 1) that allows pivoting movement of the second lower bars 16, 18 relative to the first upper bars 22, 24.
The first lower rigid bars 12, 14 are connected to metal anchor stirrups 34 (only one of which can be seen in FIG. 1) by way of a joint 36 (only one of which can be seen in FIG. 1). The anchor stirrups 34 are secured in slots 38 provided in the heel portion of a shoe 40. The joint 36 allows pivoting movement of the individual's ankle during use.
The device 10 also includes a padded tongue 42 that is secured to the pair of second upper rigid bars 26, 28 for tightening against the upper thigh of the individual. Adjustable straps 44 permit the tongue 42 to be tightened. A thigh band 46 is also provided for resting against the rear part of the upper leg portions. The lower portion of the leg rests against shin band 48. Knee cap 29 is included to rest against the individual's patella.
In order to lock the metal bars 16, 22 and 18, 24 in a vertical position (i.e., in the position shown in FIG. 1), a known locking mechanism is provided. A releasing lever 50 unlocks the locking mechanism to allow the second lower bars 16, 18 to pivot relative to the first upper bars 22, 24, thereby allowing the individual to bend his/her leg at the knee.
Medical devices of the type illustrated in FIG. 1 are typically designed to support and transfer at least a portion of the individual's body weight through the rigid metal bars 26, 28, 22, 24, 16, 18, 12, 14 and to the shoe 40. In fact, some of these devices are specifically designed to fit under the ischial tuberosity in the pelvic region so that in essence, the individual "sits" on the orthopedic device, thereby transmitting his/her body weight through the rigid metal bars 26, 28, 22, 24, 16, 18, 12, 14 and to the shoe 40. Thus, in addition to aligning the upper and lower leg portions of the individual, these devices actually serve to support a significant amount of the individual's weight.
It can be readily appreciated that devices such as those shown in FIG. 1 suffer from certain disadvantages and drawbacks. For example, the devices are quite heavy, thereby making it difficult for the individual to walk. The devices can also be cumbersome and difficult to use and care for.
The devices also suffer from the drawback that they are designed from the shoe or foot upwards, much like one would construct a building from the foundation upward. Beginning at the shoe 40, the technician or designer simply connects together the rigid metal bars of appropriate length to result in a device that is suitably sized to fit the individual. The disadvantage with this type of construction is that the materials and characteristics needed at the knee joint, for example, can differ significantly from the materials and characteristics that are needed at other portions of the leg, for example, the ankle and foot. Moreover, little attention is paid to ensuring that the device possesses sufficient rigidity in the knee area.
Known orthopedic devices of the type illustrated in FIG. 1 are also not well-suited for resisting torsional forces. That is due, at least in part, to the fact that the devices are designed with two metal bars extending along opposite sides of the leg. The inadequate nature of the devices in this regard can cause misalignment of the bones at the joints and, consequently, undesirable wear.
Another problem associated with known devices such as the one illustrated in FIG. 1 is that the rigid metal bars do not permit a relatively close contact fit with the body, particularly in the area of the knee and on either side of the knee region. As a result, an undesirable amount of "play" or motion is permitted in the axial direction (i.e., along the length of the leg). This can cause the ligaments in the knee area to become over-stretched, thereby adding to the individual's physical impairment.
Further, as noted above, the known types of devices are often designed so that the device itself actually supports a significant amount of the individual's weight. Because the load is not transferred directly through and supported by the bones and joints, there may be a tendency for the bones to atrophy. Also, because the devices are sometimes designed to contact the ischial tuberosity in the pelvic region, the skin or tissue in that area can become bruised, and sores can result.